#include<bits/stdc++.h>
using namespace std;

int main() {
	
	int n,x,y,cms ;
	int cms_eat;
	
	cin >> n >> x >> y ; // input
	
	cms_eat = y/x;
	
	if (y%x == 0 )
	{
		cms=n-cms_eat ;
	}
	else if (y%x != 0)
	{
		cms=n-cms_eat-1 ;
}
	if (cms < 0)
	{
		cout<< "0";
	}
	else
{
			cout << cms ;
}
	return 0;
}
